1. Field of the Invention
The present invention relates to, for example, a microscope system that irradiates illumination light to a specimen and acquires a specimen image generated based on light transmitted or reflected by the specimen.
2. Description of the Related Art
In the related art, a microscope system with a microscope apparatus has been used, which illuminates and observes a specimen to observe cells, and the like in a field such as medicine or biology. Further, in an industrial field, a microscope apparatus has been used for various purposes such as quality management of a metallic structure, and the like, or research and development of new materials, examination of electronic devices or magnetic heads, and the like. In addition, as a microscope system that observes a specimen, a microscope system has been known, which has a configuration that captures the specimen image by using an imaging device such as a CCD camera and displays the specimen image on a monitor, in addition to observation with naked eyes.
In the microscope system, a large amount of light needs to be radiated to the specimen in order to expansively observe a minute region of the specimen. Thus, in the microscope system, a mercury lamp or a halogen lamp is used as a light source. In many cases, the light source is attached to a back surface of the microscope system so as to prevent the observer from being interrupted when the observer observes the specimen in a comfortable position with his/her arms put on a desk, makes a memo on the desk, or the like.
For example, as illustrated in FIG. 17, a transmissive microscope system 100 in the related art includes a microscope body part 110 having substantially a C shape, a lamp house 120 attached to the microscope body part 110 and radiating illumination light for transmitting a specimen S, and an adapter 130 attached to the microscope body part 110 and guiding light (observation light) transmitting the specimen S to a lens barrel 131 or a camera 132. The microscope body part 110 includes a base portion 111 forming a foundation, an arm portion 112 extending substantially parallel to a bottom surface of the base portion 111, and a frame portion 113 connecting the ends of the base portion 111 and the arm portion 112.
The base portion 111 is connected with the lamp house 120 and ejects the illumination light from the lamp house 120 to the specimen S. The base portion 111 includes a filter insertion/removal mechanism constituted by a plurality of filters 114 holding a filter for adjusting a color tone or brightness of the light source and an illumination optical system constituted by a mirror 115 reflecting the illumination light to the specimen S, and ejects the illumination light from the lamp house 120 to the specimen S.
The arm portion 112 holds an objective lens 117 through a revolver 118 and includes therein an observation optical system provided on an optical axis of the objective lens 117. The adapter 130 connected to the arm portion 112 switches a light path to the lens barrel 131 or the camera 132 with respect to the observation light acquired from the observation optical system or branches the observation light to both sides at a ratio of 50:50.
The frame portion 113 extends vertically from the base portion 111 and has a stage 116 for placing the specimen S. The stage 116 places the specimen S and supports a condenser unit 119 having a lens that condenses the illumination light from the base portion 111 on the specimen S. The stage 116 can move vertically along the optical axis of the objective lens 117 and can move a specimen placement surface on which the specimen S is placed in a direction parallel to the surface.
The lamp house 120 includes a light source 121, a collector lens 122 collecting light radiated from the light source 121, and a heat ray absorbing filter 123 absorbing a heat ray (infrared ray).
By the aforementioned configuration, the illumination light radiated from the lamp house 120 transmits the specimen S and the transmitted light from the specimen S is transferred to the lens barrel 131 and/or the camera 132 through the objective lens 117 and the observation optical system to observe an observation image of the specimen S.
In the microscope system 100 in the related art, heat generated from the lamp house 120 (light source 121) is transferred to the base portion 111 and the frame portion 113 of the microscope body part 110 at the time of observing the specimen S and the microscope body part 110 thermally expands by the heat or heat distribution of the microscope body part 110 becomes non-uniform. As a result, the microscope body part 110 is deformed, and a distance between the stage 116 supporting the specimen S and the objective lens 117 varies from several microns to tens of microns. The variation in the distance between the stage 116 and the objective lens 117 has a large influence on a very small focal depth range and causes a focusing position adjusted once to be lost in the microscope.
In regard to the problem, for example, Japanese Patent Application Laid-open No. 2001-066514 discloses a technology that suppresses the variation in the distance between the stage and the objective lens by alleviating stretching deformation of the frame portion due to the heat with bending deformation of the arm portion. In detail, the base portion, the frame portion, and the arm portion of the microscope body part are configured as individual bodies, and respectively fixed through fastening members, and a contact area between the base portion and the frame portion is formed to be smaller than a predetermined contact area, thereby reducing heat transfer to the frame portion and the arm portion from a power supply and the illumination optical system. Alternatively, the frame portion and the arm portion are formed by materials having different thermal expansion rate.
Japanese Patent Application Laid-open No. 2001-066515 discloses a technology that includes a contact area adjusting member for reducing a contact area between the base portion and the frame portion or between the frame portion and the arm portion of the microscope body part, and suppresses the variation in the distance between the stage and the objective lens by reducing heat transfer to the frame portion from the base portion or to the frame portion from the arm portion by using the contact area adjusting member.
In addition, like a microscope system 200 illustrated in FIG. 18, by an adapter 140 connected with each of the microscope body part 110 and the lamp house 120, a distance between the microscope body part 110 and the lamp house 120 increases and heat transfer from the lamp house 120 to the microscope body part 110 is reduced.